[PATCH v2] mkdumprd: try to get mount options from fstab first

[Vivek Goyal]

On Tue, Sep 16, 2014 at 03:06:25PM +0800, Baoquan He wrote:
> On 09/15/14 at 11:09am, Vivek Goyal wrote:
> > On Thu, Sep 04, 2014 at 05:38:17PM +0800, Baoquan He wrote:
> > > Previously if a target need mount info, the relevant mount options
> > > are got from /proc/mounts by below command:
> > > findmnt -k -f -n -r -o OPTIONS $_dev
> > > 
> > > This will bring problems. Since /proc/mounts will give out a set
> > > which contains each option. Some options have value specified by
> > > user, some options just have default value if user doesn't specify.
> > > If some mount options are not supported very well, bugs occured.
> > > The more options, the worse.
> > > 
> > > So in this patch, we try to check fstab to get mount options firstly,
> > > this give user a chance to decide which options they really want.
> > > If they don't give a fstab entry, then we trust all options in
> > > /proc/mounts.
> > > 
> > > Signed-off-by: Baoquan He <bhe at redhat.com>
> > > ---
> > >  mkdumprd | 3 ++-
> > >  1 file changed, 2 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/mkdumprd b/mkdumprd
> > > index 409235b..a30d9ca 100644
> > > --- a/mkdumprd
> > > +++ b/mkdumprd
> > > @@ -104,7 +104,8 @@ to_mount() {
> > >      # mount under /sysroot in 2nd kernel, and we umount -R /sysroot before exit
> > >      _target="/sysroot$_target"
> > >      _fstype=$(findmnt -k -f -n -r -o FSTYPE $_dev)
> > > -    _options=$(findmnt -k -f -n -r -o OPTIONS $_dev)
> > > +    _options=$(findmnt --fstab -f -n -r -o OPTIONS $_dev)
> > > +    [ -z "$_options" ] && _options=$(findmnt -k -f -n -r -o OPTIONS $_dev)
> > 
> > Ok, so kernel recognizes -o defaults?
> > 
> > Secondly, question of x-systemd.* options still remains.
> 
> I just put the information of fstab in 1st kernel into fstab in 2nd
> kernel. They should handle fstab in the same mechanism. I just tested
> the -o defaults, it works. There should not be difference between 1st
> kernel and 2nd kernel.

what about x-systemd* options?

I think dracut puts them into fstab files and respective mount units
are created and that's why we don't see the failure.

Otherwise I got a feeling that if you pass x-systemd* directly to mount
command, it might fail.

Thanks
Vivek